The field of this invention is that of electronic equipment utilizing detachable electronic modules and the invention relates more particularly to racks for mounting a plurality of such modules on programmable electronic controller or process control computer systems or the like.
As the use of programmable electronic controllers and process control computers rapidly increases, it is becoming more and more common to have a substantial number of base controller units dispersed at a variety of locations around a factory and to have such base controllers coupled to a common sequencer or central processing unit. In that arrangement, it is desirable to have racks available at each of the base controller locations for use in mounting a plurality of input/output modules in detachable electrical connection with the individual base controllers. For that purpose, it is highly desirable to provide conveniently useable module racks which can be made available in substantial number at low cost but which are also adapted to provide secure and reliable mounting for the modules. The reliable mounting of the modules becomes particularly important where the modules are provided in the form of long or wide but thin packets to better accommodate module components and the like. As thus far made available, mounting racks for input/output modules for programmable controllers and the like have tended to be either expensive and somewhat inconvenient to use or to provide less than fully secure module mounting, particularly for large flat modules.